Wednesday, August 08, 2012

Livingston Bay

This log-choked salt marsh originally formed behind a tenuous spit, but sometime last century, a dike was built along the general line of the spit, cutting off tidal influence so the area could to be pastured. There have been years of debate about what to do with this site, in part to address a mosquito problem that tidal circulation would help alleviate.  Now the Nature Conservancy is excavating a portion of the old dike and restoring a tidal inlet at the northern end, which should result in much more efficient exchange and a marsh much more similar to what used to be here.

The beach here doesn't amount to much.  Iverson Spit, located a short distance south, is much larger and probably traps a bulk of the sediment transported from Barnum Point.  The limited sand on this beach may come from the reworking of older marsh or tidal flat deposits, although I suppose some sediment may find its way north from Iverson.  Up here at the north end of Port Susan, most of the wave action is from the south, across the broad flats that extend over from the Stilliguamish Delta.


Over the past few years, a new sandy spit has grown north from this site into the marsh.  In a year, the new tidal channel will wind out behind this spit.  The big question will be whether the new channel will allow all those trapped logs to escape, or whether they will simply choke the new channel until a really high tide occurs.

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